Wyniki wyszukiwania - Biblioteka Nauki

1

Optimization of alpha-galactosidase production in Streptomyces erythrus

100%

Elshafei A. M. , Foda M. S. , Abdel-Mobde E. , Ali N. H.

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nr 1

2

Isolation, identification and extracellular enzymatic activity of culturable extremely halophilic archaea and bacteria of IncheBoroun wetland

72%

Rasooli M. , Amoozegar M. A. , Sepahy A. A. , Babavalian H. , Tebyanian H.

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tom 56

EN

Extremely halophilic diversity of IncheBroun wetland located in the north of Iran was investigated by using culture-dependent methods. Sampling was carried out in May and September 2014. In each sampling 4 distinct regions of wetland were analyzed by using complex media like MGM, JCM168, MH1 and an alkaliphilic medium containing 23% salts. After incubation at 40˚C, a total of 406 isolates and 2.1 × 106 CFU/ml were obtained in culture media. Among them 361 isolates were obtained from MGM and 39 isolates from JCM 168, 3 isolates from MH1 and 3 isolates from the alkaliphilic media. Initial morphological, biochemical and physiological tests were performed. Production of 4 hydrolytic enzymes by 45 selected strains was assayed qualitatively. A total of 38, 19 and 6 strains were able to produce lipase, DNase and amylase activity. Protease activity was not observed among strains. As total 45 strains were selected randomly and phylogenetic analysis of 16S rRNA was performed for them. Among selected strains 40 isolated strians belonged to Haloarchaea and were belonged to the genera: Haloarcula(30%), Halorubrum(27.5%), Haloferax(17.5%), Halobellus (10%), Halogeometricum(5.2%), Halobacterium(2.6%), Halolamina(2.6%), Halorhabdus (2.6%) and Halostagnicola (2.6%). Haloarcula and Halorubrum were the dominant populations. A total of 5 strains belonged to domain of Bacteria and were similar to members of Rhodovibrio (40%), Pseudomonas (40%) and Salicola (20%).

3

Extracellular enzyme profiles of Xerophilic fungi isolated from dried materials of medicinal plants

72%

Janda-Ulfig K. , Ulfig K. , Markowska A.

Polish Journal of Environmental Studies

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2009

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tom 18

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nr 3

391-397

EN

Fungal extracellular enzymes may play a role in biodeterioration of dried materials of medicinal plants and in propagation of toxigenic and pathogenic fungal strains. However, no data on enzymatic activities of xerophilic fungi contaminating these materials have been found in the literature. The objective of the study was to determine extracellular enzyme profiles of slow-growing fungi, i.e. Eurotium amstelodami, E. chevalieri, E. herbariorum and Aspergillus versicolor isolated from dried materials of medicinal plants from herbal shops of Szczecin, Poland. Solid media and API ZYM® test were used to determine enzymatic activities. The highest colony diameters were observed in A. versicolor on gelatin, cellulose, tributyrin, rapeseed oil, biodiesel oil and diesel oil agars, and in E. herbariorum on milk and starch agars. A. versicolor also showed the highest hydrolytic activity on milk, gelatin, starch and tributyrin agars. No hydrolysis zones were formed on cellulose, rapeseed oil and biodiesel oil agars, but the stimulation effect of the oils on fungal growth was clearly observed. The effect was the highest in E. amstelodami, and considerably increased during a 21-day incubation period. In addition, E. amstelodami and A. versicolor showed high catalase, urease and DNA-se activities. A. versicolor had higher pectate lyase activity compared to E. amstelodami. Of the fungi examined, E. amstelodami showed the highest hydrolase activity in the API ZYM® test. A. versicolor and E. amstelodami were found to be the two species with the highest biodeterioration potential for dried materials of medicinal plants. Xerophilic fungi isolated from this environment could also be used in bioremediation.

4

Production of extracellular enzymes by Trichoderma reesei M-7 on mixtures of lactose and glucose at different temperatures

72%

Janas P. , Targonski Z. , Udeh K. O. , Wasko A.

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nr 1

EN

Continuous cultivation of Trichodcnna reesei M-7 mutant was performed at different temperatures (26, 30 and 34°C) with 1% lactose or glucose alone or a total of 1% mixtures of both sugars at different ratio. The secretion of individual enzymes was affected by the ratio of cellulase inducer (lactose) to the repressor (glucose). The ratio of enzyme secretions was additionally modified by the temperature of cultivations. An insignificant increase of nonspecific activity of cellulases (FPU) and significant increase of aryl-ß-glucosidase activity were observed at 26°C with lactose/glucose ratio of 3:1 and 1:1. However, when cultivated both at 30 or 34°C, the cellulolytic activities (FPU) increased significantly in the presence of 1% glucose alone. The activity of xylanases increased significantly (about 8-fold) with lactose/glucose ratio of 1:1 at 30°C. The increased synthesis of lytic enzymes (proteases, ß-1,3-glucanases) correlated with increased glucose concentration in the feeding medium and this effect potentiated at 34°C of cultivation.

PL

Przeprowadzono hodowle ciągłe mutanta M-7 Trichoderma reesei w różnych temperaturach w obecności 1% laktozy, 1% mieszanin laktozy z glukozą i 1% glukozy. Zmiany ilościowego stosunku induktora celulaz (laktozy ) i represora (glukozy) w odmienny sposób wpływały na sekrecję poszczególnych enzymów podczas hodowli ciągłych Trichoderma reesei M-7. Dodatkowym czynnikiem modyfikującym te proporcje była temperatura hodowli. Glukoza w stężeniu 0,25% i 0,5% przy stężeniu laktozy 0,75% i 0,5% powodowała niewielkie podwyższenie niespecyficznej aktywności celulolitycznej FPU oraz wyraźny wzrost arylo-ß-glukozydazy podczas hodowli ciągłej T. reesei M-7 w temperaturze 26°C. Podwyższenie temperatury hodowli do 30 i 34°C zwiększyło wrażliwość enzymów celulolitycznych na obecność glukozy w podłożu. Podłoże hodowlane zawierające 0,5% laktozy i 0,5% glukozy wpływało na podwyższenie aktywności enzymów ksylanolitycznych podzas hodowli ciągłej T. reesei M-7 w temperaturze 30°C. Wzrost stężenia glukozy w podłożu hodowlanym był ponadto skorelowany z podwyższeniem aktywności enzymów autolitycznych tj. proteaz i ß-1,3-glukanaz. Efekt ten był szczególnie widoczny podczas hodowli ciągłej w temperaturze 34°C.